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arXiv · 1201.0174

First-Order Reorientation of the Flux-Line Lattice in CaAlSi

P. K. Biswas·M. R. Lees·G. Balakrishnan·D. Q. Liao·D. S. Keeble·J. L. Gavilano·N. Egetenmeyer·C. D. Dewhurst·D. McK. Paul
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Abstract

The flux line lattice in CaAlSi has been studied by small angle neutron scattering. A well defined hexagonal flux line lattice is seen just above Hc1 in an applied field of only 54 Oe. A 30 degree reorientation of this vortex lattice has been observed in a very low field of 200 Oe. This reorientation transition appears to be of first-order and could be explained by non-local effects. The magnetic field dependence of the form factor is well described by a single penetration depth of 1496(1) angstroms and a single coherence length of 307(1) angstroms at 2 K. At 1.5 K the penetration depth anisotropy is 2.7(1) with the field applied perpendicular to the c axis and agrees with the coherence length anisotropy determined from critical field measurements.

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P. K. Biswas, M. R. Lees, G. Balakrishnan, D. Q. Liao, D. S. Keeble, J. L. Gavilano, N. Egetenmeyer, C. D. Dewhurst, D. McK. Paul. 2011-12-30. First-Order Reorientation of the Flux-Line Lattice in CaAlSi. https://doi.org/10.1103/physrevlett.108.077001

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